No clinical or genetic markers were found to be predictive of psoriatic arthritis in patients with psoriasis, but one laboratory marker was identified.
A new systematic literature review has located a biomarker that appears to indicate which patients with psoriasis will also suffer from psoriatic arthritis (PsA).
The report, published in Arthritis Research & Therapy, also identified markers related to inflammation and bone metabolism that appeared to be associated with PsA, but which did not reach the evidentiary value of being predictive.
Between 20% and 30% of patients with psoriasis will go on to develop PsA, but the process is slow, with about 10 years on average between the psoriasis and PsA diagnoses, wrote the investigators, including corresponding author Michelle L. M. Mulder, MSc, of the St. Martin Clinic and Radboud University Medical Center, in the Netherlands. PsA can lead to irreversible joint damage, so patients whose arthritis can be quickly identified can benefit from early treatment and the prevention of some level of damage.
A number of clinical and laboratory factors can help clinicians understand an individual patient’s risk of developing PsA, but Mulder and colleagues wanted to know whether genetic biomarkers might also be a usable avenue to more specifically identify patients likely to have or develop PsA.
The investigators searched 5 databases of existing scientific literature in May 2020. They sought studies that assessed markers associated with PsA, or the development of PsA, in patients with psoriasis. The search yielded more than 5000 studies. After winnowing down the list using eligibility criteria, they were left with a total of 119 studies, from which 259 potential markers were gleaned, including clinical, laboratory, and genetic markers.
None of the clinical or genetic markers assessed were found to have a predictive association with the development of PsA in patients with psoriasis.
Of the 137 laboratory markers assessed, just one, C-X-C motif ligand 10 (CXCL10), showed strong evidence that it was predictive of PsA. Several other biomarkers related to bone metabolism and inflammation reached the bar of “strong evidence” for an association with PsA, though they were not found to be predictive of PsA.
The authors noted that some potential markers had conflicting results in the literature. For instance, body mass index was associated with PsA in some, but not all, of the studies identified.
“In three out of five high/fair quality studies, there was no association, while two out of five showed a positive association,” Mulder and colleagues wrote.
However, they said other markers related to body weight, such as recent weight gain or abdominal adiposity, were found to have a positive association with PsA, but they were only investigated in a single, low-quality study.
The investigators said one of the strengths of their study was that they not only looked at the findings of existing trials, but also incorporated qualitative data in order to focus on the best available evidence.
Limitations of the study included a relative lack of high- and fair-quality studies and a low number of prospective or longitudinal studies.
The researchers said their study provides a clear picture of the current scientific knowledge, but said additional research is needed to better predict PsA.
“The importance of timely detecting PsA in a Pso population, and finding more (bio)markers contributing to early detection, remains high,” they concluded.
Mulder MLM, van Hal TW, Wenink MH, et al. Clinical, laboratory, and genetic markers for the development or presence of psoriatic arthritis in psoriasis patients: a systematic review. Arthritis Res Ther. Published online June 14, 2021. doi:10.1186/s13075-021-02545-4